Carbon arms with M30 (30mm drive/28mm non-drive) aluminum spindle- Cold forged, proprietary LevaTime II X-rings (104/160BCD) with steel chainring bolts- *M30 BB sold separately, use PX9040 for English 68mm, PX9011 for BB30/PF30 or PX9013 for PF86.5 BBs, PX-9014 for BBright, PX9015 for 386EVO, PX9016 for T47 external and PX9017 for T47 internal- BB tool sold separately, use PX8980/8981- Direct Mount (DM) 1x not available- For additional Praxis 2x chainring options, use PX211*- Works with 10/11sp drivetrains, not compatible at this time with SRAM AXS chain- Weight without BB: 684g (172.5mm with 50/34)